Spark-gap.



ED sTATEs PATENT OFFICE.

FRED H. KROGER, OF BROOKLYN, NEW YORK, ASSIGNOR TO SAMUEL M. KIN'TNER AND HALSEY M. BARRETT, RECEIVERS FOR THE NATIONAL ELECTRIC SIGNALING COM- IPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF NEW JERSEY. Y

SPARK-GASP.

Speeication of Letters Patent.

Patented Aug. 1, 1916.

Application filed August 31, 1914. Serial No. 859,432.

' to spark gaps for generating oscillations in wireless telegraph, apparatus and particularly the so-called quenchedfgap for this A purpose. Its primary objects are to avoid the necessity of inclosing the sparking surfaces in an air-tight chamber and. to causea discharge to take place uniformly by traveling over continually cooled surfaces.

I have illustrated the invention in the accompanying drawing in which the figure is a sideelevation partially in section on the left of the gap proper.

The usual form of the quenched spark gap, has been inclosed and the sparking electrodes stationary, but I have found that under proper conditions the gap need not beA closed and has certain additional advantages hereinafter to be noted, when4 not inclosed.

In the accompanying drawing I mount l upon the supports 1 and 2, the shaft 3'which is divided between the supports and on the sleeves 4 carries an insulating tube 5, upon which, clamped between screw thimbles 6 are the sparking plates 7, separated by insulating rings 8. These rings 'or washers 8V are carefully selected to give the proper separation between adjacent plates and it lwill be understood that the plates thusinsulated from each other are carefully trued on alathe and mounted to be perfectly parallel. The electric contact to the end plates of the series may be made through the binding posts-9 and 10 on shaft 3. I .Y

The shaft 3 and the sparking plates 7 are caused to slowly rotate by means of worm gearing 15, 16, 14, 13, the latter being on the shaft 12L of a small motor 12, which is also used to operate a fan ll'having a flared horn or nozzle l1a to distribute the air and blow it between and around the disks 7.

The horn 11a, of the fan 11 is made of insulating material and serves as a dielectric or electrostatic attractor which has the effect of concentrating the lines of force in the electrostatic ield and causing the spark to occur near said dielectric 'and therefore 4to travel over the surface of the. plates 7, as thely slowly rotatepast the insulating materia The construction described has several advantages, among which are the great ease of inspecting and cleaning; the traveling of the charge around the circumference of the disks, thereby securing uniformity; and the Y gap becomes noisy and the sparking does occur at the edges. This gives the operator a constant' reminder of the state of his tuning, which is a very valuable quality.

'Other advantages'of the device will readily occur to those skilled in the art.

What I claim is: 1. A spark gap, comprising a series of ini sulated disk electrodes in parallel planes and arranged to rotate on a common axis, and a statlonary dielectric near the peripheries of salddisks and having longitudinally extendto c ause the sparks to substantially remain statlonary as the disks. revolve.

2. A -spark gap, comprising a series of .ingportions opposite the gaps therebetween I parallel disks insulated from each other and Y v.mounted on a shaft, means for rotating said shaft, a blower, and a nozzle connected there-vv toto-distribute air between and around said disks, said nozzle beingmade of insulating material and mounted near the edge of the disks and serving as a dielectric to cause the spark to travel'over the surfaces of the disks as the.v disks revolve.

3. In wireless telegraphy apparatus, a. quenched spark gap, comprising a rotating1 insulated shaft, a series of Hat-faced disks insulated from each other on said shaft, a device tocontinually cool said disks, and a.

' continuous dielectric opposite the edges of said disks to govern the position of the sparks on the disks as they revolve.

In testimony whereof, I have hereunto set my hand. FRED H. KRUGER. 

